1. Field of the Invention
The present invention concerns a pointing device or cursor control device such as a mouse, which controls movement of the cursor on a computer display by entering positional information into a computer.
2. Related Art
Because it is very difficult for users to interact with a computer system using a large keyboard, a mouse used as a pointing device has been developed to control the movement of the cursor on the computer display. Moreover, if the user wants to control the cursor on the display of a computer system operated in a graphic user interface, it is very inconvenient for him to enter positional information into the computer. The mouse generally comprises a small housing with two or three buttons on the top used to indicate that desired positions have been reached, and a sensor built into the underside of the housing which is rolled around on any flat surface. Its direction of movement is sensed and transmitted to the computer, which translates the movement into cursor movement on the display screen.
Conventional pointing devices suffer various drawbacks including the fact that it is very difficult to achieve a precise cursor movement, especially in drawing a straight line. This means that the conventional pointing devices are not adequate to effectively manage the entering of positional information into the computer. Furthermore, their size serves as a limitation in reducing the size of the notebook computer.
The following patents each disclose features in common with the present invention: U.S. Pat. No. 4,712,101 to Culver, entitled CONTROL MECHANISM FOR ELECTRONIC APPARATUS, U.S. Pat. No. 4,823,634 to Culver, entitled MULTIFUNCTION TACTILE MANIPULATABLE CONTROL, U.S. Pat. No. 4,724,715 to Culver, entitled CONTROL MECHANISM FOR COMPUTER KEYBOARD AND THE LIKE, U.S. Pat. No. 4,896,554 to Culver, entitled MULTIFUNCTION TACTILE MANIPULATABLE CONTROL, U.S. Pat. No. 4,982,618 to Culver, entitled MULTIFUNCTION TACTILE MANIPULATABLE CONTROL, U.S. Pat. No. 5,666,138 to Culver, entitled INTERFACE CONTROL, U.S. Pat. No. 4,763,116 to Eichholz, entitled INPUT APPARATUS FOR DESIGN WORK ON AN IMAGE-BEARING SCREEN, U.S. Pat. No. 5,563,631 TO Masunaga, entitled PORTABLE INFORMATION APPARATUS, and U.S. Pat. No. 5,644,337 to Stacy, entitled TRACKBALL HAVING SINGLE EMITTER-DETECTOR DETECTING CHOPPER WHEEL DIRECTION.